The prevalence of smoking among individuals seeking treatment for a co-occurring substance abuse condition is very high, between 70%-95% (Burling &Ziff, 1988;Fiore et al., 2000;Kozlowski et al., 1986;McCarthy et al., 2002). However, many drug treatment facilities do not encourage smoking cessation during treatment, even though patients are often show interest in quitting smoking. Research finds that not only are low income people more likely to smoke, but the resources for smoking cessation may not be as accessible as those who have higher income (Novotny &Giovino, 1998;MMRW, November 9, 2007;Barbeau et al., 2004;Honjo et al., 2006). Therefore, substance abuse treatment is a context where evidence-based treatments (EBTs) for smoking might have the best chance of reaching low-income smokers. Treating patient smoking concurrent with other drugs is important since research demonstrates that addiction to nicotine may cause changes in brain chemistry and structure which could trigger drug and alcohol cravings, decreasing the chance of prolonged sobriety (Britt &McGehee, 2008;Yeh et al., 2007). The proposed project pursues two objectives related to understanding the adoption, implementation, and sustainability (or conversely discontinuation) of EBTs for smoking in substance abuse treatment contexts. The first aim examines longitudinally the availability of EBTs for smoking among those seeking treatment for co-occurring substance abuse and explores the predictors of changes in service availability over time in treatment programs. Key categories of predictors include the percentage of low-income clients served by the treatment center, organizational and policy factors, and workforce characteristics. The second aim also uses a longitudinal design to examine the evidence-based clinical practice behaviors that counselors engage in with clients. This is important because individuals implement EBTs not organizations or treatment programs (Fixsen et al., 1995). Integrating theory and research from implementation science, public health, organizational change, substance abuse treatment, and health services delivery four categories of moderator variables are examined to understand why and under what conditions counselors are likely to engage clients in smoking cessation efforts with clients. PUBLIC HEALTH RELEVANCE: The health-related risks of smoking make it a major public health concern, particularly in light of recent research suggesting that the addictive properties of nicotine are similar to that of opiates. There are also health disparities in both smoking behavior and smoking treatment as a function of socio-economic status and race/ethnicity. Many low-income people also lack access to high quality medical care (Warnecke et al., 2008) and are over-represented in substance abuse treatment contexts. By focusing on the availability, implementation, and sustainability of evidence-based treatments for smoking in the context of substance abuse treatment the proposed application has clear public health (including public health policy) relevance.